A double-pole, double-throw relay with actuating mechanism driven by a momentary-power, twin coil solenoid. (A solenoid is a cylindrical coil of insulated wire in which an iron core is made to move back and forth by a flow of electric current.) With just a few simple connections, this small device, which may be mounted anywhere, can:

• Power the frogs on Atlas' Mark 3 & Code 83 #6 turnouts
• Control trackside signal lamps to show turnout point positions
• Operate control panel lamps to show settings of remotely located turnouts (switches)
• Provide selective track siding control. Sidings are powered only when points are aligned for siding. Siding remains dead when points are set for the mainline.
• Control X-sections automatically. This very useful track arrangement is thoroughly discussed in Atlas' Complete Wiring Book.